Carlton forward Levi Casboult sustained a fractured rib and will spend around four weeks on the sidelines following a nasty collision with Adelaide defender Tom Doedee in the dying stages of the Blues' loss to the Crows on Saturday night.

With just minutes remaining in the match, Casboult went up for a mark while Doedee's knee hit Casboult in the ribs, which saw the big key forward hit the ground in some pain.

“Scans have also confirmed as a result of the fracture, Levi has sustained an injury to the lining of his lung,” Carlton's Head of Football Andrew McKay told carltonfc.com.au.

“Levi will remain in Adelaide for monitoring over the coming days and while disappointing that this adds to our growing injury list, we understand that senior exposure will only benefit our younger players in the long-term.”